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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Network143.0.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
143.0.0.0
Broadcast address
143.7.255.255
First usable
143.0.0.1
Last usable
143.7.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
B (default /16)
As numbers
Hex 8F000000 · Integer 2399141888 to 2399666175
Reverse DNS zones
0.143.in-addr.arpa
1.143.in-addr.arpa
2.143.in-addr.arpa
3.143.in-addr.arpa
4.143.in-addr.arpa
5.143.in-addr.arpa
6.143.in-addr.arpa
7.143.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10001111.00000000.00000000.00000000143.0.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network10001111.00000000.00000000.00000000143.0.0.0
Broadcast10001111.00000111.11111111.11111111143.7.255.255
Split into smaller subnets/22
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

143.0.0.0/13 makes 512 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1143.0.0.0/22143.0.0.1 to 143.0.3.254143.0.3.2551,022
2143.0.4.0/22143.0.4.1 to 143.0.7.254143.0.7.2551,022
3143.0.8.0/22143.0.8.1 to 143.0.11.254143.0.11.2551,022
4143.0.12.0/22143.0.12.1 to 143.0.15.254143.0.15.2551,022
5143.0.16.0/22143.0.16.1 to 143.0.19.254143.0.19.2551,022
6143.0.20.0/22143.0.20.1 to 143.0.23.254143.0.23.2551,022
7143.0.24.0/22143.0.24.1 to 143.0.27.254143.0.27.2551,022
8143.0.28.0/22143.0.28.1 to 143.0.31.254143.0.31.2551,022
9143.0.32.0/22143.0.32.1 to 143.0.35.254143.0.35.2551,022
10143.0.36.0/22143.0.36.1 to 143.0.39.254143.0.39.2551,022
11143.0.40.0/22143.0.40.1 to 143.0.43.254143.0.43.2551,022
12143.0.44.0/22143.0.44.1 to 143.0.47.254143.0.47.2551,022
13143.0.48.0/22143.0.48.1 to 143.0.51.254143.0.51.2551,022
14143.0.52.0/22143.0.52.1 to 143.0.55.254143.0.55.2551,022
15143.0.56.0/22143.0.56.1 to 143.0.59.254143.0.59.2551,022
16143.0.60.0/22143.0.60.1 to 143.0.63.254143.0.63.2551,022
17143.0.64.0/22143.0.64.1 to 143.0.67.254143.0.67.2551,022
18143.0.68.0/22143.0.68.1 to 143.0.71.254143.0.71.2551,022
19143.0.72.0/22143.0.72.1 to 143.0.75.254143.0.75.2551,022
20143.0.76.0/22143.0.76.1 to 143.0.79.254143.0.79.2551,022
21143.0.80.0/22143.0.80.1 to 143.0.83.254143.0.83.2551,022
22143.0.84.0/22143.0.84.1 to 143.0.87.254143.0.87.2551,022
23143.0.88.0/22143.0.88.1 to 143.0.91.254143.0.91.2551,022
24143.0.92.0/22143.0.92.1 to 143.0.95.254143.0.95.2551,022
25143.0.96.0/22143.0.96.1 to 143.0.99.254143.0.99.2551,022
26143.0.100.0/22143.0.100.1 to 143.0.103.254143.0.103.2551,022
27143.0.104.0/22143.0.104.1 to 143.0.107.254143.0.107.2551,022
28143.0.108.0/22143.0.108.1 to 143.0.111.254143.0.111.2551,022
29143.0.112.0/22143.0.112.1 to 143.0.115.254143.0.115.2551,022
30143.0.116.0/22143.0.116.1 to 143.0.119.254143.0.119.2551,022
31143.0.120.0/22143.0.120.1 to 143.0.123.254143.0.123.2551,022
32143.0.124.0/22143.0.124.1 to 143.0.127.254143.0.127.2551,022
33143.0.128.0/22143.0.128.1 to 143.0.131.254143.0.131.2551,022
34143.0.132.0/22143.0.132.1 to 143.0.135.254143.0.135.2551,022
35143.0.136.0/22143.0.136.1 to 143.0.139.254143.0.139.2551,022
36143.0.140.0/22143.0.140.1 to 143.0.143.254143.0.143.2551,022
37143.0.144.0/22143.0.144.1 to 143.0.147.254143.0.147.2551,022
38143.0.148.0/22143.0.148.1 to 143.0.151.254143.0.151.2551,022
39143.0.152.0/22143.0.152.1 to 143.0.155.254143.0.155.2551,022
40143.0.156.0/22143.0.156.1 to 143.0.159.254143.0.159.2551,022
41143.0.160.0/22143.0.160.1 to 143.0.163.254143.0.163.2551,022
42143.0.164.0/22143.0.164.1 to 143.0.167.254143.0.167.2551,022
43143.0.168.0/22143.0.168.1 to 143.0.171.254143.0.171.2551,022
44143.0.172.0/22143.0.172.1 to 143.0.175.254143.0.175.2551,022
45143.0.176.0/22143.0.176.1 to 143.0.179.254143.0.179.2551,022
46143.0.180.0/22143.0.180.1 to 143.0.183.254143.0.183.2551,022
47143.0.184.0/22143.0.184.1 to 143.0.187.254143.0.187.2551,022
48143.0.188.0/22143.0.188.1 to 143.0.191.254143.0.191.2551,022
49143.0.192.0/22143.0.192.1 to 143.0.195.254143.0.195.2551,022
50143.0.196.0/22143.0.196.1 to 143.0.199.254143.0.199.2551,022
51143.0.200.0/22143.0.200.1 to 143.0.203.254143.0.203.2551,022
52143.0.204.0/22143.0.204.1 to 143.0.207.254143.0.207.2551,022
53143.0.208.0/22143.0.208.1 to 143.0.211.254143.0.211.2551,022
54143.0.212.0/22143.0.212.1 to 143.0.215.254143.0.215.2551,022
55143.0.216.0/22143.0.216.1 to 143.0.219.254143.0.219.2551,022
56143.0.220.0/22143.0.220.1 to 143.0.223.254143.0.223.2551,022
57143.0.224.0/22143.0.224.1 to 143.0.227.254143.0.227.2551,022
58143.0.228.0/22143.0.228.1 to 143.0.231.254143.0.231.2551,022
59143.0.232.0/22143.0.232.1 to 143.0.235.254143.0.235.2551,022
60143.0.236.0/22143.0.236.1 to 143.0.239.254143.0.239.2551,022
61143.0.240.0/22143.0.240.1 to 143.0.243.254143.0.243.2551,022
62143.0.244.0/22143.0.244.1 to 143.0.247.254143.0.247.2551,022
63143.0.248.0/22143.0.248.1 to 143.0.251.254143.0.251.2551,022
64143.0.252.0/22143.0.252.1 to 143.0.255.254143.0.255.2551,022
65143.1.0.0/22143.1.0.1 to 143.1.3.254143.1.3.2551,022
66143.1.4.0/22143.1.4.1 to 143.1.7.254143.1.7.2551,022
67143.1.8.0/22143.1.8.1 to 143.1.11.254143.1.11.2551,022
68143.1.12.0/22143.1.12.1 to 143.1.15.254143.1.15.2551,022
69143.1.16.0/22143.1.16.1 to 143.1.19.254143.1.19.2551,022
70143.1.20.0/22143.1.20.1 to 143.1.23.254143.1.23.2551,022
71143.1.24.0/22143.1.24.1 to 143.1.27.254143.1.27.2551,022
72143.1.28.0/22143.1.28.1 to 143.1.31.254143.1.31.2551,022
73143.1.32.0/22143.1.32.1 to 143.1.35.254143.1.35.2551,022
74143.1.36.0/22143.1.36.1 to 143.1.39.254143.1.39.2551,022
75143.1.40.0/22143.1.40.1 to 143.1.43.254143.1.43.2551,022
76143.1.44.0/22143.1.44.1 to 143.1.47.254143.1.47.2551,022
77143.1.48.0/22143.1.48.1 to 143.1.51.254143.1.51.2551,022
78143.1.52.0/22143.1.52.1 to 143.1.55.254143.1.55.2551,022
79143.1.56.0/22143.1.56.1 to 143.1.59.254143.1.59.2551,022
80143.1.60.0/22143.1.60.1 to 143.1.63.254143.1.63.2551,022
81143.1.64.0/22143.1.64.1 to 143.1.67.254143.1.67.2551,022
82143.1.68.0/22143.1.68.1 to 143.1.71.254143.1.71.2551,022
83143.1.72.0/22143.1.72.1 to 143.1.75.254143.1.75.2551,022
84143.1.76.0/22143.1.76.1 to 143.1.79.254143.1.79.2551,022
85143.1.80.0/22143.1.80.1 to 143.1.83.254143.1.83.2551,022
86143.1.84.0/22143.1.84.1 to 143.1.87.254143.1.87.2551,022
87143.1.88.0/22143.1.88.1 to 143.1.91.254143.1.91.2551,022
88143.1.92.0/22143.1.92.1 to 143.1.95.254143.1.95.2551,022
89143.1.96.0/22143.1.96.1 to 143.1.99.254143.1.99.2551,022
90143.1.100.0/22143.1.100.1 to 143.1.103.254143.1.103.2551,022
91143.1.104.0/22143.1.104.1 to 143.1.107.254143.1.107.2551,022
92143.1.108.0/22143.1.108.1 to 143.1.111.254143.1.111.2551,022
93143.1.112.0/22143.1.112.1 to 143.1.115.254143.1.115.2551,022
94143.1.116.0/22143.1.116.1 to 143.1.119.254143.1.119.2551,022
95143.1.120.0/22143.1.120.1 to 143.1.123.254143.1.123.2551,022
96143.1.124.0/22143.1.124.1 to 143.1.127.254143.1.127.2551,022
97143.1.128.0/22143.1.128.1 to 143.1.131.254143.1.131.2551,022
98143.1.132.0/22143.1.132.1 to 143.1.135.254143.1.135.2551,022
99143.1.136.0/22143.1.136.1 to 143.1.139.254143.1.139.2551,022
100143.1.140.0/22143.1.140.1 to 143.1.143.254143.1.143.2551,022
101143.1.144.0/22143.1.144.1 to 143.1.147.254143.1.147.2551,022
102143.1.148.0/22143.1.148.1 to 143.1.151.254143.1.151.2551,022
103143.1.152.0/22143.1.152.1 to 143.1.155.254143.1.155.2551,022
104143.1.156.0/22143.1.156.1 to 143.1.159.254143.1.159.2551,022
105143.1.160.0/22143.1.160.1 to 143.1.163.254143.1.163.2551,022
106143.1.164.0/22143.1.164.1 to 143.1.167.254143.1.167.2551,022
107143.1.168.0/22143.1.168.1 to 143.1.171.254143.1.171.2551,022
108143.1.172.0/22143.1.172.1 to 143.1.175.254143.1.175.2551,022
109143.1.176.0/22143.1.176.1 to 143.1.179.254143.1.179.2551,022
110143.1.180.0/22143.1.180.1 to 143.1.183.254143.1.183.2551,022
111143.1.184.0/22143.1.184.1 to 143.1.187.254143.1.187.2551,022
112143.1.188.0/22143.1.188.1 to 143.1.191.254143.1.191.2551,022
113143.1.192.0/22143.1.192.1 to 143.1.195.254143.1.195.2551,022
114143.1.196.0/22143.1.196.1 to 143.1.199.254143.1.199.2551,022
115143.1.200.0/22143.1.200.1 to 143.1.203.254143.1.203.2551,022
116143.1.204.0/22143.1.204.1 to 143.1.207.254143.1.207.2551,022
117143.1.208.0/22143.1.208.1 to 143.1.211.254143.1.211.2551,022
118143.1.212.0/22143.1.212.1 to 143.1.215.254143.1.215.2551,022
119143.1.216.0/22143.1.216.1 to 143.1.219.254143.1.219.2551,022
120143.1.220.0/22143.1.220.1 to 143.1.223.254143.1.223.2551,022
121143.1.224.0/22143.1.224.1 to 143.1.227.254143.1.227.2551,022
122143.1.228.0/22143.1.228.1 to 143.1.231.254143.1.231.2551,022
123143.1.232.0/22143.1.232.1 to 143.1.235.254143.1.235.2551,022
124143.1.236.0/22143.1.236.1 to 143.1.239.254143.1.239.2551,022
125143.1.240.0/22143.1.240.1 to 143.1.243.254143.1.243.2551,022
126143.1.244.0/22143.1.244.1 to 143.1.247.254143.1.247.2551,022
127143.1.248.0/22143.1.248.1 to 143.1.251.254143.1.251.2551,022
128143.1.252.0/22143.1.252.1 to 143.1.255.254143.1.255.2551,022
129143.2.0.0/22143.2.0.1 to 143.2.3.254143.2.3.2551,022
130143.2.4.0/22143.2.4.1 to 143.2.7.254143.2.7.2551,022
131143.2.8.0/22143.2.8.1 to 143.2.11.254143.2.11.2551,022
132143.2.12.0/22143.2.12.1 to 143.2.15.254143.2.15.2551,022
133143.2.16.0/22143.2.16.1 to 143.2.19.254143.2.19.2551,022
134143.2.20.0/22143.2.20.1 to 143.2.23.254143.2.23.2551,022
135143.2.24.0/22143.2.24.1 to 143.2.27.254143.2.27.2551,022
136143.2.28.0/22143.2.28.1 to 143.2.31.254143.2.31.2551,022
137143.2.32.0/22143.2.32.1 to 143.2.35.254143.2.35.2551,022
138143.2.36.0/22143.2.36.1 to 143.2.39.254143.2.39.2551,022
139143.2.40.0/22143.2.40.1 to 143.2.43.254143.2.43.2551,022
140143.2.44.0/22143.2.44.1 to 143.2.47.254143.2.47.2551,022
141143.2.48.0/22143.2.48.1 to 143.2.51.254143.2.51.2551,022
142143.2.52.0/22143.2.52.1 to 143.2.55.254143.2.55.2551,022
143143.2.56.0/22143.2.56.1 to 143.2.59.254143.2.59.2551,022
144143.2.60.0/22143.2.60.1 to 143.2.63.254143.2.63.2551,022
145143.2.64.0/22143.2.64.1 to 143.2.67.254143.2.67.2551,022
146143.2.68.0/22143.2.68.1 to 143.2.71.254143.2.71.2551,022
147143.2.72.0/22143.2.72.1 to 143.2.75.254143.2.75.2551,022
148143.2.76.0/22143.2.76.1 to 143.2.79.254143.2.79.2551,022
149143.2.80.0/22143.2.80.1 to 143.2.83.254143.2.83.2551,022
150143.2.84.0/22143.2.84.1 to 143.2.87.254143.2.87.2551,022
151143.2.88.0/22143.2.88.1 to 143.2.91.254143.2.91.2551,022
152143.2.92.0/22143.2.92.1 to 143.2.95.254143.2.95.2551,022
153143.2.96.0/22143.2.96.1 to 143.2.99.254143.2.99.2551,022
154143.2.100.0/22143.2.100.1 to 143.2.103.254143.2.103.2551,022
155143.2.104.0/22143.2.104.1 to 143.2.107.254143.2.107.2551,022
156143.2.108.0/22143.2.108.1 to 143.2.111.254143.2.111.2551,022
157143.2.112.0/22143.2.112.1 to 143.2.115.254143.2.115.2551,022
158143.2.116.0/22143.2.116.1 to 143.2.119.254143.2.119.2551,022
159143.2.120.0/22143.2.120.1 to 143.2.123.254143.2.123.2551,022
160143.2.124.0/22143.2.124.1 to 143.2.127.254143.2.127.2551,022
161143.2.128.0/22143.2.128.1 to 143.2.131.254143.2.131.2551,022
162143.2.132.0/22143.2.132.1 to 143.2.135.254143.2.135.2551,022
163143.2.136.0/22143.2.136.1 to 143.2.139.254143.2.139.2551,022
164143.2.140.0/22143.2.140.1 to 143.2.143.254143.2.143.2551,022
165143.2.144.0/22143.2.144.1 to 143.2.147.254143.2.147.2551,022
166143.2.148.0/22143.2.148.1 to 143.2.151.254143.2.151.2551,022
167143.2.152.0/22143.2.152.1 to 143.2.155.254143.2.155.2551,022
168143.2.156.0/22143.2.156.1 to 143.2.159.254143.2.159.2551,022
169143.2.160.0/22143.2.160.1 to 143.2.163.254143.2.163.2551,022
170143.2.164.0/22143.2.164.1 to 143.2.167.254143.2.167.2551,022
171143.2.168.0/22143.2.168.1 to 143.2.171.254143.2.171.2551,022
172143.2.172.0/22143.2.172.1 to 143.2.175.254143.2.175.2551,022
173143.2.176.0/22143.2.176.1 to 143.2.179.254143.2.179.2551,022
174143.2.180.0/22143.2.180.1 to 143.2.183.254143.2.183.2551,022
175143.2.184.0/22143.2.184.1 to 143.2.187.254143.2.187.2551,022
176143.2.188.0/22143.2.188.1 to 143.2.191.254143.2.191.2551,022
177143.2.192.0/22143.2.192.1 to 143.2.195.254143.2.195.2551,022
178143.2.196.0/22143.2.196.1 to 143.2.199.254143.2.199.2551,022
179143.2.200.0/22143.2.200.1 to 143.2.203.254143.2.203.2551,022
180143.2.204.0/22143.2.204.1 to 143.2.207.254143.2.207.2551,022
181143.2.208.0/22143.2.208.1 to 143.2.211.254143.2.211.2551,022
182143.2.212.0/22143.2.212.1 to 143.2.215.254143.2.215.2551,022
183143.2.216.0/22143.2.216.1 to 143.2.219.254143.2.219.2551,022
184143.2.220.0/22143.2.220.1 to 143.2.223.254143.2.223.2551,022
185143.2.224.0/22143.2.224.1 to 143.2.227.254143.2.227.2551,022
186143.2.228.0/22143.2.228.1 to 143.2.231.254143.2.231.2551,022
187143.2.232.0/22143.2.232.1 to 143.2.235.254143.2.235.2551,022
188143.2.236.0/22143.2.236.1 to 143.2.239.254143.2.239.2551,022
189143.2.240.0/22143.2.240.1 to 143.2.243.254143.2.243.2551,022
190143.2.244.0/22143.2.244.1 to 143.2.247.254143.2.247.2551,022
191143.2.248.0/22143.2.248.1 to 143.2.251.254143.2.251.2551,022
192143.2.252.0/22143.2.252.1 to 143.2.255.254143.2.255.2551,022
193143.3.0.0/22143.3.0.1 to 143.3.3.254143.3.3.2551,022
194143.3.4.0/22143.3.4.1 to 143.3.7.254143.3.7.2551,022
195143.3.8.0/22143.3.8.1 to 143.3.11.254143.3.11.2551,022
196143.3.12.0/22143.3.12.1 to 143.3.15.254143.3.15.2551,022
197143.3.16.0/22143.3.16.1 to 143.3.19.254143.3.19.2551,022
198143.3.20.0/22143.3.20.1 to 143.3.23.254143.3.23.2551,022
199143.3.24.0/22143.3.24.1 to 143.3.27.254143.3.27.2551,022
200143.3.28.0/22143.3.28.1 to 143.3.31.254143.3.31.2551,022
201143.3.32.0/22143.3.32.1 to 143.3.35.254143.3.35.2551,022
202143.3.36.0/22143.3.36.1 to 143.3.39.254143.3.39.2551,022
203143.3.40.0/22143.3.40.1 to 143.3.43.254143.3.43.2551,022
204143.3.44.0/22143.3.44.1 to 143.3.47.254143.3.47.2551,022
205143.3.48.0/22143.3.48.1 to 143.3.51.254143.3.51.2551,022
206143.3.52.0/22143.3.52.1 to 143.3.55.254143.3.55.2551,022
207143.3.56.0/22143.3.56.1 to 143.3.59.254143.3.59.2551,022
208143.3.60.0/22143.3.60.1 to 143.3.63.254143.3.63.2551,022
209143.3.64.0/22143.3.64.1 to 143.3.67.254143.3.67.2551,022
210143.3.68.0/22143.3.68.1 to 143.3.71.254143.3.71.2551,022
211143.3.72.0/22143.3.72.1 to 143.3.75.254143.3.75.2551,022
212143.3.76.0/22143.3.76.1 to 143.3.79.254143.3.79.2551,022
213143.3.80.0/22143.3.80.1 to 143.3.83.254143.3.83.2551,022
214143.3.84.0/22143.3.84.1 to 143.3.87.254143.3.87.2551,022
215143.3.88.0/22143.3.88.1 to 143.3.91.254143.3.91.2551,022
216143.3.92.0/22143.3.92.1 to 143.3.95.254143.3.95.2551,022
217143.3.96.0/22143.3.96.1 to 143.3.99.254143.3.99.2551,022
218143.3.100.0/22143.3.100.1 to 143.3.103.254143.3.103.2551,022
219143.3.104.0/22143.3.104.1 to 143.3.107.254143.3.107.2551,022
220143.3.108.0/22143.3.108.1 to 143.3.111.254143.3.111.2551,022
221143.3.112.0/22143.3.112.1 to 143.3.115.254143.3.115.2551,022
222143.3.116.0/22143.3.116.1 to 143.3.119.254143.3.119.2551,022
223143.3.120.0/22143.3.120.1 to 143.3.123.254143.3.123.2551,022
224143.3.124.0/22143.3.124.1 to 143.3.127.254143.3.127.2551,022
225143.3.128.0/22143.3.128.1 to 143.3.131.254143.3.131.2551,022
226143.3.132.0/22143.3.132.1 to 143.3.135.254143.3.135.2551,022
227143.3.136.0/22143.3.136.1 to 143.3.139.254143.3.139.2551,022
228143.3.140.0/22143.3.140.1 to 143.3.143.254143.3.143.2551,022
229143.3.144.0/22143.3.144.1 to 143.3.147.254143.3.147.2551,022
230143.3.148.0/22143.3.148.1 to 143.3.151.254143.3.151.2551,022
231143.3.152.0/22143.3.152.1 to 143.3.155.254143.3.155.2551,022
232143.3.156.0/22143.3.156.1 to 143.3.159.254143.3.159.2551,022
233143.3.160.0/22143.3.160.1 to 143.3.163.254143.3.163.2551,022
234143.3.164.0/22143.3.164.1 to 143.3.167.254143.3.167.2551,022
235143.3.168.0/22143.3.168.1 to 143.3.171.254143.3.171.2551,022
236143.3.172.0/22143.3.172.1 to 143.3.175.254143.3.175.2551,022
237143.3.176.0/22143.3.176.1 to 143.3.179.254143.3.179.2551,022
238143.3.180.0/22143.3.180.1 to 143.3.183.254143.3.183.2551,022
239143.3.184.0/22143.3.184.1 to 143.3.187.254143.3.187.2551,022
240143.3.188.0/22143.3.188.1 to 143.3.191.254143.3.191.2551,022
241143.3.192.0/22143.3.192.1 to 143.3.195.254143.3.195.2551,022
242143.3.196.0/22143.3.196.1 to 143.3.199.254143.3.199.2551,022
243143.3.200.0/22143.3.200.1 to 143.3.203.254143.3.203.2551,022
244143.3.204.0/22143.3.204.1 to 143.3.207.254143.3.207.2551,022
245143.3.208.0/22143.3.208.1 to 143.3.211.254143.3.211.2551,022
246143.3.212.0/22143.3.212.1 to 143.3.215.254143.3.215.2551,022
247143.3.216.0/22143.3.216.1 to 143.3.219.254143.3.219.2551,022
248143.3.220.0/22143.3.220.1 to 143.3.223.254143.3.223.2551,022
249143.3.224.0/22143.3.224.1 to 143.3.227.254143.3.227.2551,022
250143.3.228.0/22143.3.228.1 to 143.3.231.254143.3.231.2551,022
251143.3.232.0/22143.3.232.1 to 143.3.235.254143.3.235.2551,022
252143.3.236.0/22143.3.236.1 to 143.3.239.254143.3.239.2551,022
253143.3.240.0/22143.3.240.1 to 143.3.243.254143.3.243.2551,022
254143.3.244.0/22143.3.244.1 to 143.3.247.254143.3.247.2551,022
255143.3.248.0/22143.3.248.1 to 143.3.251.254143.3.251.2551,022
256143.3.252.0/22143.3.252.1 to 143.3.255.254143.3.255.2551,022

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.